Highly functionalized cyclic and bicyclic β−amino acids from sugar β−nitroesters

The synthesis of highly functionalized bicyclic and cyclic β-amino acids from β-nitrosugars is reported. Specifically, our strategy for the synthesis of polyhydroxylated cyclopentane β-amino acids via the intramolecular C-alkylation of 6-nitro-2-O-triflates of furanosides has been applied to the preparation of the first two examples of a novel class of bicyclic β-amino acids and a novel cyclopentene β-amino acid. Also, our Henry reaction mediated strategy for the synthesis of polyhydroxylated cyclohexane β-amino acids has been extended to a divergent, stereoselective synthesis of new polysubstituted cyclohexane and cyclopentane β-amino acids.